Genetic genealogy testing company FamilyTreeDNA has launched a mitochondrial-DNA database called MitoSearch <www.mitosearch.org>. The free site lets you enter results from any testing company and search for mitochondrial DNA (also called mtDNA) matches. Tests of mtDNA, which is passed from mother to child, reveal “deep ancestry” and can give information on ethnic origins. Results assign you to a haplogroup — the equivalent of a maternal branch in the world's family tree.

MitoSearch contains data from nearly 500 individuals, and allows side-by-side comparisons of those results. Users also can upload GEDCOM files (the universal file format for family trees). FamilyTreeDNA spokesperson Max Blankfeld says that viewing the pedigrees helps when you're looking for women who may have gotten married and changed their last names.

FamilyTreeDNA also operates Ysearch, a database of approximately 10,000 people's Y-DNA test results. Blankfeld expects MitoSearch to grow more slowly than Ysearch. “Far fewer people test their mtDNA compared to Y-DNA,” he explains. See the February 2005 Family Tree Magazine for a layperson's guide to genetic genealogy.